Fix spelling error in distorts index.html

Fix typo in distorts page. s/web size/website/

Author: kruton

distorts/index.html

@@ -2893,7 +2893,7 @@ <h4>Example Depolar-Polar Effects</h4>So lets again show better <b>Polar Rotatio
               </tr>
             </table>See also <a href="../advanced/#stars">Stars and Comets</a> for another example of doing this, but directly generating the intermediate 'DePolar' image, before applying a '<code><a href="#polar">Polar</a></code>' distortion.Special thanks goes to <a href="http://www.fmwconcepts.com/fmw/fmw.html">Fred Weinhaus</a> for the special uses of a DePolar-Polar cycle, and for insisting that I ensure that these distortions were fully reversible for rectangular images. He puts this technique to good effect in a number of his <a href="http://www.fmwconcepts.com/imagemagick/index.html">ImageMagick Scripts</a>, including "<code><a href="http://www.fmwconcepts.com/imagemagick/bump/index.php">bump</a></code>", "<code><a href="http://www.fmwconcepts.com/imagemagick/ripples/index.php">ripples</a></code>", and "<code><a href="http://www.fmwconcepts.com/imagemagick/striations/index.php">striations</a></code>".<br>
             <a name="barrel" id="barrel"></a>
-            <h3>Barrel Distortion <font size="-1">(correcting lens distortions)</font></h3>The Barrel Distortion (added to IM v6.4.2-4) is designed specifically for correcting the spherical distortions caused by camera lenses in photos. That is distortions such as barrel and pincushion effects, which are effectively the reverse of each other. For actual application of using this operator for lens distortion correction see the section, <a href="../#lens">Lens Correction</a>. The distort is implemented based on a set of 4 coefficient values, known as <code>A</code>, <code>B</code>, <code>C</code>, and <code>D</code>, as defined by <a href="http://webuser.fh-furtwangen.de/~dersch/">Professor Helmut Dersch</a>, in a web size that has since vanished. You can see a <a href="http://waybackmachine.org/web/web.php">Wayback Machine</a> archive of the site at <a href="http://replay.waybackmachine.org/20090613040829/http://www.all-in-one.ee/~dersch/barrel/barrel.html">Correcting Barrel Distortion</a>. The values basically form a distortion equation such that...
+            <h3>Barrel Distortion <font size="-1">(correcting lens distortions)</font></h3>The Barrel Distortion (added to IM v6.4.2-4) is designed specifically for correcting the spherical distortions caused by camera lenses in photos. That is distortions such as barrel and pincushion effects, which are effectively the reverse of each other. For actual application of using this operator for lens distortion correction see the section, <a href="../#lens">Lens Correction</a>. The distort is implemented based on a set of 4 coefficient values, known as <code>A</code>, <code>B</code>, <code>C</code>, and <code>D</code>, as defined by <a href="http://webuser.fh-furtwangen.de/~dersch/">Professor Helmut Dersch</a>, in a website that has since vanished. You can see a <a href="http://waybackmachine.org/web/web.php">Wayback Machine</a> archive of the site at <a href="http://replay.waybackmachine.org/20090613040829/http://www.all-in-one.ee/~dersch/barrel/barrel.html">Correcting Barrel Distortion</a>. The values basically form a distortion equation such that...
             <div align="center">
               <code><i>R<sub>src</sub></i> = r * ( A*<i>r<sup>3</sup></i> + B*<i>r<sup>2</sup></i> + C*<i>r</i> + D )</code>
             </div>Where "<code><i>r</i></code>" is the destination radius and "<code><i>R<sub>src</sub></i></code>" is the source pixel to get the pixel color from. the radii are normalized so that radius = '<code>1.0</code>' for the half minimum width or height of the input image. This may seem reversed but that is because the <a href="#mapping">Reverse Pixel Mapping</a> technique is used to ensure complete coverage of the resulting image. All four coefficients (<code>A</code>, <code>B</code>, <code>C</code>, and <code>D</code>) are fixed for any specific camera, lens, and zoom, combination. All three of which is typically stored with the image in a <a href="../photos/#exif">EXIF Profile</a>. This is important as it means that once you have these values for your camera you can use them to remove the spherical lens distortion that is present in all the photos taken by that camera and lens combination. The arguments needed for the '<code><b>Barrel</b></code>' distort method. Generally you supply 3 or 4 values only...